I/o control with vcl – Wesley BC-620-4CA User Manual
Page 91
Curtis 1234/36/38 Manual,
OS
11
87
2 3 J U LY 2 0 0 8 D R A F T
VCL RUNTIME RATES
VCL is an interpreted language. Each line of VCL code is converted (compiled)
into a set of codes and then flash loaded into the controller. The controller
interprets these codes one line at a time while the system is powered up. Here
are the processing rates of the various functions:
FUNCTION
FUNCTION
FULL
NAME
INSTANCES
SERVICE
RATE
ABS
Absolute Value
2
4 ms
ADC
Analog to Digital Converter Input
2
1 ms
CAN
CAN Communications
15
4 ms
CPY
Copy
8
4 ms
DLY
Delay
32
1 ms
FLT
Filter
4
1 ms
LIM
Limit
4
4 ms
MAP
Map
4
4 ms
MTD
Multiply then Divide
4
4 ms
NVM
Non-Volatile Memory
38
2 ms
PID
Proportional Integral Derivative
2
4 ms
POT
Potentiometer Input
2
8 ms
PWM
Pulse Width Modulated Output
6
4 ms
RMP
Ramp
4
1 ms
SCL
Scaling
4
4 ms
SEL
Selector, 2-position switch
8
4 ms
SEL_4P
Selector, 4-position switch
8
32 ms
SW
Switch Input
1
*
4 ms
TMR
Timers (hourmeters)
3
1 ms
*
There is only one Switch variable; it has 16 associated bit-variables.
I/O CONTROL WITH VCL
Digital Inputs
The 1234 controller has at total of 16 digital inputs, and the 1236/38 has 15.
Eight are switch inputs (Sw_1 through Sw_8) on all the models; the 1234 has
a ninth switch input, Sw_16. These switch inputs are shown on the standard
wiring diagram (Figure 3, page 12). The remaining seven digital inputs are less
obvious: one on each driver and digital output (Sw_9 through Sw_15). These
can be used as digital inputs or to sense the state of the output or its wiring
(e.g., open coil check).
To address a digital input in a VCL program, use the desired input label
(Sw_1 through Sw_16). You must use On or Off in the code when determining
a switch state; using true/false or 1/0 will give erroneous results.
7 — VCL